The present invention relates to a trailing-type rear wheel suspension system, and more particularly, to a trailing arm mounting structure, in which rear wheels follow a path approximating rectilinear motion in an upward/rearward and downward/forward direction during bump and rebound of the vehicle body.
In a trailing-type rear wheel suspension system, one end of a trailing arm is connected to a rear wheel and its other end is mounted to a vehicle body. Accordingly, during bump and rebound of the vehicle body, the rear wheel connected to the trailing arm follows a path drawn upwardly and downwardly about a mounting point of the trailing arm, that is, the point at which the trailing arm is mounted to the vehicle body. During rebound in an upward direction of the vehicle body, the rear wheels move according to a downward/forward path, and during bump in a downward direction of the vehicle body, the rear wheels move according to an upward/forward path.
However, as a result of the forward motion of the rear wheels during bump of the vehicle body, shock received from the road in the forward and rear direction is directly transmitted to the vehicle body. Also, such a path of the rear wheels reduces the amount of space available for the back seat as well as for the fuel tank.
According to the present invention, a trailing arm mounting structure is provided, in which the rear wheels follow a path approximating a straight line, which forms a predetermined acute angle with the road surface to the rear of the vehicle. During bump and rebound of the vehicle body shock in forward and rearward directions transmitted from the road is thereby reduced and space provided for the backseat and fuel tank is increased.
In a preferred embodiment of the present invention, a first end of the trailing arm is connected to a rear wheel and a second end of the trailing arm is connected to the vehicle body with a concoid curve-forming assembly interposed therebetween. The concoid curve-forming assembly preferably comprises a link, interposed between the vehicle body and the second end of the trailing arm, and a bushing, connected to the vehicle body and the trailing arm at a distance spaced from the second end of the trailing arm sufficient to permit concoid motion of the vehicle body and of the trailing arm. The bushing enables the second end of the trailing arm to form a concoid curve during operation of the trailing arm mounting structure. The bushing provides an axis about which the trailing arm pivots and enables the trailing arm to move in a direction of its long axis.
The link preferably comprises a first mounting point, where the link is connected to the vehicle body, and a second mounting point, where the link is connected to the second end of the trailing arm. The second mounting point is most preferably at an extreme end of the trailing arm, and the first mounting point is at a predetermined distance from the second mounting point.